Fasting diets could raise risk of diabetes say experts

Br Dr Ananya Mandal, MD

One of the new fangled diets include fasting frequently to lose weight. A team of researchers speaking at the European Society of Endocrinology’s annual meeting at Barcelona last weekend have said that this could be severely detrimental to health.

Image Credit: Ekaterina Markelova / Shutterstock
Image Credit: Ekaterina Markelova / Shutterstock

According to their research findings, the team noted that these diets based on frequent or alternate day fasting could damage the way sugar-regulating hormone insulin works in the body. Frequent fasting can alter insulin function and secretion and raise the risk of getting diabetes they warn. Ana Bonassa and her team from University of São Paulo in Brazil, in their study looked at the health effects of these fasting diets.

Bonassa explains that this is the first study that looks deep into the effects of fasting diet on health. She explains that fasting intermittently can damage the pancreas. The pancreas is responsible for secreting insulin hormone in normal healthy individuals. this could lead to diabetes and other health problems she added.

Intermittent fasting diets have become a weight-watchers’ mantra these days say researchers with many people swearing by it. There is a 5:2 diet, where the participants fast for two days in a week on alternate days. The long term effects of this type of diet were hitherto unknown. There have been studies that show that on fasting, in the short term too there can be health risks. For example fasting can lead to production of free radicals that are highly reactive and can cause damage to the cells and tissues. These free radicals have been implicated in causing cancer, long term diseases and also accelerating the ageing process.

This latest study looked at the effects of fasting on alternate days on the changes in body weight and also levels of free radicals in blood and insulin function. They tested this on normal adult rats for three months. They noted that over time the fasting diet reduced the amount of food that the rats were taking but the fat around the bellies actually increased. Further, the intermittent fasting had caused damage to the cells of the pancreas that release insulin. This led to insulin resistance and low amounts of insulin. Free radical levels rose too with the fasting diet regimen.

According to Bonassa, this study gives a fair idea of what these diets are doing to humans. In the long term this diet may be causing more harm than we know now she added. She explained that people who are overweight or obese may already have insulin resistance. When they adopt the fasting diet, they just worsen their condition. Insulin resistance is tied to development of type 2 diabetes she said. The diet works initially by helping in dramatic weight loss initially but the damage occurs in the long term Bonassa explained.

Type-2 diabetes is one of the major health problems worldwide and is associated with poor diet and inactive lifestyles. It is linked to obesity and insulin resistance intricately.

Dr. Ananya Mandal

Written by

Dr. Ananya Mandal

Dr. Ananya Mandal is a doctor by profession, lecturer by vocation and a medical writer by passion. She specialized in Clinical Pharmacology after her bachelor's (MBBS). For her, health communication is not just writing complicated reviews for professionals but making medical knowledge understandable and available to the general public as well.


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